Caster



l, 1931. w. G. JOHNSON Sept.

GASTER Filed Sept. 16, 1929 INVENTOR.

Patented Sept. 1, 1931 narran sTaTes 'WIIFRED Gr. JOHNSON, OF ELYBIA,OHIO,

'ELYRIA, OER),L A CORPORATION OF OHO PATENT @Trice Assis-Noa To annconsona comparar, or

Cns'rnn Application filed September 16, 1929. Serial No. 393,077.

This inventionv relates to casters.

' One of the objects of this invention is to provide a caster which willbe cheap to manufacture, simple to construct and assemble and durableand eflcient in operation.

Another object is to provide va caster having an improved anti-frictionswivel'bearing.

Another object is to provide a caster having an improved swivel bearingof the ball Another object is to provide a caster having a swivelbearing of the balltype from whichvdirt, etc. may be excluded from andlubricant retained in the bearing. n

Another object is to provide a. caster having swivel bearing of the balltype, the balls of which are enclosed and shielded in an improvedmanner.

Another Objectis to provide a caster having swivel ball bearing, inwhich the fit between the balls and the races may be conveniently andeasily adjusted during the assembling of the bearing or subsequently totake up wear.

Another object is to provide a caster having an antifriction swivelbearing of theball and race type, of which the balls and races may beenclosed within an integrally formed chamber adapted to permit easyassembling of the parts of the bearing through apertures of the chamber.

Other objects will skilled in this art.

My invention is fully disclosed inthe folbe apparent to those lowingdescription taken in connection with the accompanying drawings, in whichF ig. 1 is a side sectional view of a caster embodying my invention withsome ofthe parts shown in elevation;

Fig. 2 is an elevational View of the caster of Fig. 1 taken from thefront thereof;

Fig. '3 is an individual lview of theparts shown in Fig. 1.

l/Vhile my invention is applicable to casters of various types, lhave'chosen to illustrate and describe itin connection with a caster ofthe so-called stem type. i

At 1 is indicated the stem by which the caster may be attached to orconnected with the piece of furniture or other article to be cylindricalhaving a cylindrical side wall 9;

and its upper end is closed by a generally circular top walllO inwhichthe perforation 6 is provided. IThe chamber 30 thus provided isdownwardly open having'in the lower floor 35 thereof the relativelylarge perforation 11. 1t is through the perforation 11 that the rivetedhead 7 above described may be formed, and that 1searing parts areinserted into the chamber to be assembled. kA perforation 26 in the wall9 of the chamber is provided to admit bearing balls to be described.

The upper and lower circular corners between the. top wall 10 and sidewall 9 and between'the Aside wall Q-and the floor 35 are rounded7 thusproviding on the inner surface orinner walls of the chamber 30 an upperand a lower internal ball race way 12 and-13; that is'r to say, theseupper and lower circular corners ofy the chamber are made to conform tocircular profiles, in planes through the ystem axis or swiveling axisand serve as race ways, thus providing a very simple race wayconstruction.

An upper race element 14C is provided comprising a generally washershaped head portion 15 having on its upper side at its periphery a raceway 16 and being connected to a downwardly axially extending screwthreaded stud 17. The stud 17 extends downwardly out through theperforation V11 ofr the chamber and on through a suitable perforation 18in the transverse portion 19 of the yoke 3 3.

Threaded on the stud 17 is a lower race element 20 of generalcylindrical form, shown Vseparately in F ig. 3 and having its externalcylindricalk surface turned down, as at 21, to form a race way 22.

Between the race way 16 and the race way 12 is a circular row of steelbearing balls 23, and between the race way 22 and the race way 13 isanother row of steel bearing balls 24.

The race way 16 is so shaped and proportioned that when in engagementwith the balls 23, as illustrated the'lincs of action through the balls23 are Yin the general di7 rection of the line ai; and correspondingly,the lines of action through :the balls 24 are in the direction of theline y, as will be understood.

In assembling the parts of the bearing thus far described, after theVstem 1 is riveted in place, as described, the stem and chamber e30 arepreferably turned upside down; the balls 23 are inserted rinto thechamber 30 through the perforation 11 in the wall 35 of the chamber anddispose themselves around the rivet head 7. Y

The race element 14 is then inserted through the perforation 11 in thebottom of the chainber, the outside diameter of the element 14 beingsuitably proportioned to pass through the perforation 11, and the raceway 16 is rested upon the lballs 28. f

Next, the race element 20 is threaded onto the stud 17 until it'comessubstantially into engagement with the race element'14. The balls 24 areYthen passed through the perforations 26 until they rest upon the raceway 22. i

The race way 20 is then reversely screwed on the stud 17 separating thetwo race ele- Y 17, the clearance or fit between each set of balls 23and24 and the race ways thereof may bc adjusted. n f

The yokefS-S may now be attached passing the Stud 17 through theperforation 18 in the transverse portion 19 of the yoke and screwing nut28 on the free end ofthe stud clamping the transverse portion 19 of Ytheyoke lirmly against the lower squared end 29 of the race element 20.

To turn the race element 2O on the threaded stud 17 tool slots 331 maybe provided in the lower end 29 of the race element 20.

As will be understood at any time after assembly the parts may easily bedisassembled by Vremovin g the nut 28 or similarly they may be adjustedto adjust the lit of the balls in their races or to remove Vparts forrenewal.

Lubricant may be inserted into the interior of the chamber 30 throughthe perforation 26 and if desired the perforation 26 may be sealed witha: plug in any suitable er known manner. It will be observed that by thecon struction of the chamber all of the'fparts of the bearing are coverd or'shrouded and dust and dirtcannot gain access thereto:V

Furthermore, by the arrangement of thc balls and their races load on thestem 1 will be rigidly supported and by suitably proportioning thevertical dimension of the chamber 30 the lateral thrusts transmittedfrom the Wheel 2 will be absorbed by the ball bearings without lostmotion. If preferred, the supported load may rest directly upon thechamber 8O upon a suitable washer 32.

It will be observed that after the bearing has been once adjusted asabove described, the screwing up tight of the nut 28 will lock the adjustmentagainst accidental change, the nut 28 and the race element 20serving as lock nut-s on the stud 17.

In assembling the parts of the bearing, if preferred, the race element20 may be screwed upon the stud 17 into engagement with the race element14 before the latter is inserted into the chamber, this being analternative mode of assembling.

In order to contribute to compactness of design and to insure clearancebetween the rivet head 7 and the race element 14, the upper surface ofthe race element 14 is preferably cupped out, as indicated by the dottedline at 36 in Fig. l.

Having thus described my invention in a preferred embodiment, I ainaware that numerous and extensive departures may be made therefrom, butwithout departing from the spirit of my invention.

I claim:

1. In a caster, a tubular housing terminated at its ends in in urnedannular flanges, providing a pair of longitudinally spaced race ways atthe inner surfaces of the adj oining inner lateral and inner end angewalls, a caster wheel yoke element, a threaded stud projecting outwardlyfrom the intermediate portion of said yoke element, a bearing race conescrew threaded onto said stud and having a radial flange disposed withinthe tubular casing and a tubular iiange extending through an end ofthecasing, a` set of bearing balls disposed in contact with one of saidracing faces and cooperating ball race surfaces formed by adjoiningportions of said cone radial flange and tubular flange, a second set ofbearing balls for the other casing race and a cooperating bearingelement having ball bearing race surfaces for the latter set of ballssupported by said threaded stud.

2. In a ball bearing construction, a housing,a pair of axially alignedspaced circular ball race Ways in the housing, a pair of spaced race wayelements in the housing, the race way elements each providing a ballrace way, the race ways in the race elements being` aX- ially alignedwith the race ways in the housing and disposed between the latter, aplurality of balls between one of the race ways iin the housing and oneof the race ways in the race elements, a plurality of balls between'theother two race Ways, means for adjusting the relative aXial position ofthe race elements to vary the clearance between the balls and the raceways.

3. In a caster, a tubular housing terminat` ed at its ends in inturnedannular' flanges, providing a pair of longitudinally spaced race ways atthe inner surfaces of the adj oining inner lateral and inner end flangewalls, a caster wheel yoke element, a threaded stud projecting outwardlyfrom the intermediate portion of said yoke element, a bearing race conescrew threaded onto said stud and having a radial flange disposed withinthe tubular casing and a ytubular flange extending through an end of thecasing, a set of bearing balls disposed in contact with one of saidracing faces and cooperating ball race surfaces formed by adjoiningportions of said cone radial flange and tubular flange, a second set ofbearing balls for the other casing race and a cooperating bearingelement having ball bearing race surfaces for the latter set of ballssupported by said threaded stud, and a caster pintle rigidly secured tosaid casing and extending from an end thereof oppositely to said stud.

4. A bearing comprising a pair of relatively rotatable oppositelyextending elements,

a tubular bearing ball casing supported by an end wall on one of saidelements, said casing terminating at its opposite end in an annularinturned flange, and providing at its opposite ends interiorly disposedlongitudinally spaced axially aligned bearing ball races, a pair of setsof bearing balls for each of said races and separate bearing raceelements for each of said sets of bearing balls, one of said elementsscrew threaded onto a stem portion of the other element and affixedthereby to the other one of said pair of oppositely extending relativelyrotatable elements.

5. In a caster, a load supporting element, a caster yoke, a perforationin the yoke, a stud extending through the perforation, a

nut on one side of the perforation, a nut race y element on the otherside of the perforation, the nut race element, yoke and nut and studbeing adapted to be rigidly locked together by screwing the nut on thestud, a race way on the nut race element, a head on the stud, a race wayon the head, a housing connected to the load supporting element, acylindrical wall of the housing, coaxial with the stud, an upper and alower wall of the housing, at the opposite ends of the cylindrical wall,race ways in the corners between the two end walls and the cylindricalwall and balls in the race ways. c

6. In a casterv wheel bearing mechanism, the combination with a casterfork including a fork yoke, a bolt projected from within the forkoutwardly through the yoke, anut on the outside of the yoke clamping thebolt thereto and providing a bearing race on its outer surface, anannular flange for said nut towards its outerend portion forming atleast a part of said race, a disk carried on the end of said bolt,beyondy said nut and a tubular bearing cage having inturned end flangesenclosing said nut and disk, and two sets of bearing balls within thecage, one intermediate the lower inner surfaces of said cage, and saidbearing race surfaces of said nut, the other intermediate the uppersurfaces of said disk andk inner upwardly disposed surfaces of saidcage.

In testimony whereof I hereunto affix my signature this 27th day ofAugust, 1929.

WILFRED G. JOHNSON.

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